Igniters for gas generators of the conventional type consist of a housing sealed off with a base and of ignition agents incorporated in the housing, the ignition agents being ignited by a glow wire, a thin-film element or a semiconductor bridge. The ignition means are frequently made up of a primary charge and a booster charge with which the actual gas-generating mixture is made to ignite. Igniters of this type cannot be miniaturized because of their design principle. Therefore, they sometimes no longer meet the demands of the automotive industry for components that take up little installation space.
DE 198 15 928 A1 discloses a semiconductor igniter for use in a gas generator for safety systems in vehicles, with a semiconductor layer that is situated on a carrier with a thermal insulating layer in-between, whose end is connected to electric contact areas and that heats up when current passes through the ignition segment area, thereby initiating the ignition. The thermal insulating layer is limited to the ignition segment area and preferably consists of porous silicon. In order to boost the ignition, an explosive gas or gas mixture can be incorporated into the porous silicon.
It is known from Physical Review Letters 87/6 (2001), pp. 068301/1 to 068301/4 that a spontaneous explosion occurs when liquid oxygen is brought together with porous silicon that has been produced by electrochemically etching silicon in an electrolyte containing hydrogen fluoride.
Adv. Mater., 2002, 14, No. 1, pp. 38 to 41 reports that only a freshly made, porous silicon mixed with gadolinium nitrate (Gd(NO3)3.6H2O) can be made to explode through friction with a diamond tip or by an electrical spark discharge. The porous silicon mixed with gadolinium nitrate is used here as a source of energy for atom emission spectroscopy. Additional proposed applications pertain to the use as an actuator in micro-electromechanical systems.
In view of the foregoing, the invention is based on the object of providing a microelectronic-pyrotechnical component, especially for safety applications in vehicles, that is simply structured and that can be manufactured at low cost.